This invention relates to trolleys or rolling hangers, such as are used in so-called overhead trolley conveyor systems and the like such as include oppositely paired trolley wheels arranged to roll along support rails such as the bottom flanges of I-beams, or the like. Such trolley devices typically employ generally U-shaped yoke means fabricated of multiple parts to suspend from the trolley wheels to engage the dependent load.
The invention deals specially with the reality that standard production type I-beams are invariably of different flange sectional profile, notwithstanding that they are conventionally manufactured and purchased under identical "specifications". This is because such items are produced on different rolling mills at domestic and/or foreign factories operating under different design "standards"; and although in each case the rolls thereof are initially shaped to produce a "specified" size and shape (sectional form) of I-beam, because of the constantly increased wear effects on the rolls throughout their working "lives" they in fact never do produce any two or more I-beams of identical flange sectional profiles.
Heretofore trolley wheels for such purposes have of course been tread-profile-designed so as to be best suited to the "specified" flange profile upon which they are designated to be used; although as explained hereinabove no two I-beams of the same "specifications" present to the trolley wheels the identically same slope configurations. In consequence, the industry has been beset by the problem that prior trolley devices have been not only propense to undue operational deterioration/destruction, but also cause premature destruction of the flanges of the trolley support beam. In fact, with a view to more economically furnishing the conveyor industry with a suitable "universal" type trolley device adapted to provide reasonably efficient and economical service while riding on any of a variety of either flat or sloped surfaces, some manufacturers have been furnishing such devices with trolley wheels which are composites of flat and sloped profile tread configurations, which obviously provide only compromise attempts to answer the problem.